Electrical receptacle



March 26, 1963 i A. J. NIELSEN, JR 3,083,351

ELECTRICAL RECEPTACLE Filed April 10, 1961 United States Patent 3,933,351 ELECTREQAL RhKILiTACLE Anise: J. Nielset, 3n, Bailey Road, Holden, Mass. Filed a n. 11 1 261, er. No. 161,852 6 Claims. (6%. 33-21'7) The invention relates to electrical connectors and more particularly to a female connector or receptacle.

Usually a complete electrical connector consists of a male and female member, each inserted and retained within an individual insulating terminal block. Sometimes the terminal block houses a plurality of many different sizes due to the power requirements. When the terminal blocks are joined together, all the various circuits are made at the same time.

However, it is important that the female connector engage its proper mating male connector to prevent cross circuiting and malfunction of the apparatus served by them.

In use the connections are sometimes repeatedly broken and remade many times, which increases the possibility of making an improper circuit.

The female connector of the instant invention positively reduces the possibility of cross circuits by preventing an improperly mated male connector from entering it. Briefly, the invention comprises a female electrical connector of one piece construction made from sheet metal. The female connector is substantially a thin Walled metal tube with an expandable slotted tapered portion. At the end of the tube are means for contacting and fastening a conductor thereto. Adjacent the tapered portion of the tube is a seamless flared portion with an opening of a predetermined size which limits the entrance to the proper male connector for which it is usually custom made and prevents a male connector of larger size from entering. The small end of the expandable tapered portion has an opening therethrough of a size which is smaller than the opening in the flared portion and the size of the male insert, providing good contact with the male insert at all times.

Heretofore female connectors of similar type have been made which had a continuous seam throughout its length which was undesirable because it allowed the entrance portion to readily enlarge, allowing a male connector of larger size to enter it resulting in cross circuiting.

Other types were constructed which included additional parts to prevent expansion thereof, but this became too costly and time consuming.

The female connector of the instant invention is of a unique, one piece construction and can be easily manufactured economically in great quantities, faster by utilizing sheet material blanked out and formed by dies in presses or multiple slide machines customarily used in working sheet metal.

It is therefore the primary object of the invention to provide a female connector which positively prevents the insertion therein of a male connector of larger size than its proper mate.

Another object of the invention is to provide a female connector of one piece construction that can easily and economically be formed out of sheet material. Another object of the invention is to provide a female electrical connector made of sheet metal that has a seamless entrance portion. Another object is to provide a mating female connector having an integrally formed flared entrance portion which cannot be expanded in normal use.

A further object of the invention is to provide a female connector having an expandable portion for maintaining good contact with a mating male connector or insert. A further object is to provide a connector with means for preventing the ejection of the connector from a ter- 3,083,351 Z-atented Mar. 26, 1963 minal block whenever an improper male insert of a larger size, that cannot enter, is forced against its entrance.

Other objects and advantages of the instant invention Will be apparent from the following specification and reference to the accompanying drawings in which:

FIG. 1 is an enlarged isometric View of the preferred embodiment of the invention;

FIG. 2 is a sectional view taken on line 22 of FIG. 1, looking toward the entrance;

FIG. 3 is a sectional view taken on line 3-3 of FIG. 1, looking toward the entrance;

FIG. 4 is a sectional view taken on line 4-4 of FIG. 1, looking toward the conductor fastening means;

FIG. 5 is a vertical sectional view through a typical insulating terminal block, enclosing a female connector of the instant invention and also shows in phantom lines a terminal block enclosing a male connector mating with the female connector;

FIG. 6 is a plan view of a blank stamped from sheet metal from which the female connector is formed;

FIG. 7 is a sectional View showing how the seamless entrance portion is drawn and formed before it is bent upwardly;

FIG. 8 is a view looking from the right hand end of FIG. 7 showing how the body of the female connector is preformed into two integrally connected halves; and

FIG. 9 is a vertical section through the flared entrance portion showing the metal fold therein and how the expandable tapered portion overlaps the flared portion.

Referring to the drawings, the female connector or receptacle 10 comprises a straight or cylindrical portion 12 formed to a seam 14, and has a bore 16 therethrough. Extending from the cylindrical portion 12 and tapering inwardly toward the axis of the bore 16 is a slotted tapered or conical portion 18. The small end 20 of the tapered portion 18 has an opening 22 which is smaller in size than that of the mating male insert it comes in contact with.

A slot 24 through the walls of the female connector 10 extends longitudinally from the small end 20 of the tapered portion 18 to a point within the straight or cylindrical portion 12. This construction splits the tapered portion 18 into upper and lower portions and permits the upper portion to expand or move outwardly when a mating male connector is inserted therein, providing good contact with the male insert due to the fact that the material tends to spring back constantly maintaining contact with the male insert.

Integral with the lower portion of the tapered portion 18 at the small end 20 is a seamless flared or cone shaped portion 26 which forms the entrance to the female con nector 10. Unlike the straight or cylindrical portion 12 it does not have a seam even though it is formed from sheet material. Therefore, it cannot expand in normal use.

The flared portion 26 has an opening 28 through it of a predetermined size closely fitting the mating male insert. It is thus seen that by providing an unyielding flared portion with 'a custom sized hole therein, the insertion therein of a male insert of larger size is prevented, greatly reducing the possibility of making an undesirable connection. It also serves to guide the male insert when it is desired to make a connection.

Means are provided for making contact with and for fastening a conductor to the female connector 10, comprising a pair of integrally formed tangs 30 and 32, crimped about a conductor 34 and its insulation or covering 36 respectively in a customary manner.

It is also advantageous but not always necessary or desirable, to provide means by which the connector 10 is retained within an insulating terminal block without the necessity of initially molding the female connector therein and from which it can never be removed or replaced. plurality of spaced projections 4a and 42 protruding above the exterior surface of the straight portion 12 of the female connector. The projections 40 are located atthe junction of the tapered portion 18 and the straight :portion 12. However, when the tapered portion is expanded, the projections a) also move outwardly since the slot 24 extends beyond the tapered portion.

On the small end of the upper half of the tapered portion .313 is a raised or upwardly bent portion 29 which partially overlaps the exterior surface of the flared portion. The purpose of this construction is to provide additional support for the flared or cone portion 26, and also serves to cause the upper half of the tapered portion 18 to move outwardly in the event a male insert of larger size, which cannot enter, is forced against the flared portion 26. When this happens it increases the holding power of the projections 49 above the exterior surface of the female connector 10, preventing its ejection from the insulating terminal block 38.

When inserting the female connector into the terminal block 38, the projections 40 are depressed by engagement with the surface of the bore 44 and will spring outwardly when they enter the clearance hole 46 for engagement with a surface 48. The projections 42 prevent further movement into the terminal block 38 by engaging a surface 50.

When it is desired to remove a female connector 10, a tube with an internal hole of a size slightly smaller than the bore 44 is slipped over the connector 19 depressing the projections 40.

A method of making the female connector 10 with an integral seamless flared or cone shaped portion is by using sheet material, for example, .014 thick, 7(l30, hard brass, which is economical and easily formed, and by utilizing well known sheet metal working machinery of high production equipped with suflicient dies, such as a progressive die made especially for producing the instant invention.

Referring to FIGS. 6, 7, 8, and 9, sheet material is first stamped out and pierced forming a blank 10a of the general outline shown in FIG. 6 including the projections 40 and 42 and an integral flat circular portion 264 with a hole 28a through it, which is to become the flared or cone portion 26. The opening 28a at this time is of a much smaller size than the finished opening 28.

The connector is then formed as shown'in FIG. 7 and FIG. 8 in progressive steps which include preforming the cylindrical straight portion 12 and the tapered portion 18 in two semi-circular portions 12a and 12b, deep drawing the cone shaped portion 26 to finished size in the fashion shown in FIG. 7, then swinging the flared or cone shaped portions 26 from the horizontal position into the final position into axial alignment with the cylindrical portion 12 by bending the material about the portion 26b.

It willbe noted that the lower portion of flared portion 26 is partially comprised of two layers of material which is clearly shown in FIG. 9 forming a fold at 26c.

Thereafter the semi-circular portion 12b is swung about a point 120 forming the complete cylindrical straight portion 12 and the tapered portion 18 with its upper portion overlapping the exterior surface of the flared portion 26.

Simple means to accomplish this comprise a I claim: l. An integral hollow electrical receptacle split along a portion of its length comprising:

a relatively yieldable portion and a relatively fixed portion diametrically opposite one another; and

a continuous annular entrance portion adjacent the relatively fixed portion having, a relatively larger leading edge and a relatively smaller trailing edge, folded solely at and around a portion of the said leading edge into and adjacent the internal surface of a similarly shaped mating portion of the said relatively fixed portion.

2. An electrical receptacle of one piece construction formed from sheet material comprising:

a hollow cylindrical portion adapted for attaching a conductor thereto;

a split tapered portion extending from the hollow cylindrical portion including, a relatively resilient semi-circular portion arranged to maintain contact with and be sprung outwardly by a male insert, and a relatively fixed semi-circular portion;

a seamless flared entrance portion adjacent the split tapered portion, folded back into and against the said relatively fixed semi-circular portion, providing a single fold of integral material around a portion of the seamless flared entrance portion; and

a custom size hole for a mating male insert in the seamless flared entrance portion.

3. An integral electrical receptacle comprising:

a straight circular portion;

means for fastening and contacting a conductor on the straight circular portion;

means projecting above the external surface of the straight circular portion to retain the receptacle within a terminal block;

hollow expandable tapered portion extending from the straight circular portion;

a seamless flared entrance portion adjacent the hollow expandable tapered portion, folded back into and against an integral similarly shaped portion, integral with the hollow expandable tapered portion, providing a double layer of integral material around a portion of the seam-less flared entrance portion;

a hole in the seamless flared entrance portion; and

an opening in the hollow expandable tapered portion of smaller size than the size of the said hole and of the mating male insert.

4. An integral hollow electrical female connector for mounting within a terminal block comp-rising:

a straight portion;

means for fastening and contacting a conductor on the straight portion;

resilient means projecting above the external surface of the straight portion for retaining the connector in the terminal block;

a tapered portion extending inwardly from the straight portion;

means for maintaining contact with a male insert on the tapered portion;

a seamless cone shaped portion adjacent the tapered portion of a diameter, no larger than the longest cross sectional dimension of the said straight portion, and folded back into and adjacent to an integral mating cone shaped sector, integral with the tapered portion; and

a custom sized hole in the seamless cone shaped portion substantially in axial alignment with the said straight portion.

5. An integral tubular electrical receptacle comprising:

a straight portion;

a seam in the straight portion;

deformable means for contacting and fastening a conductor on the said straight portion;

a split tapered portion extending inwardly and axially from the said straight portion comprising, a relatively yieldable portion and a relatively fixed portion; spaced resilient means on the said straight and tapered portions projecting above the exterior surface of the straight portion, for preventing axial movement of the receptacle when mounted within a terminal block;

a continuous cone shaped entrance portion of smaller diameter than the said straight portion axially adjacent the said tapered portion, and said cone shaped portion folded back along a portion of its largest diameter into and against a mating portion integral with the said relatively fixed portion, with the smallest diameter of the said cone shaped portion nearest the said tapered portion;

a hole of a predetermined size in the continuous cone shaped portion for accommodating a mating male insert of a predetermined maximum size;

an opening in the tapered portion adjacent the said smallest diameter of the continuous cone shaped entrance portion, of a size less than that of the said hole of predetermined size and of the mating male insert; and

a portion of the said relatively yieldable portion overlapping, and in mating engagement with an exterior portion of the said continuous cone shaped portion.

6. An integral thin walled tubular electrical receptacle for a mating male connector adapted for mounting within a terminal block comprising: a straight circular portion including a seam; means for fastening and eontacting an electrical conductor adjacent one end of the straight circular portion; a split circular tapered portion tapering inwardly from the end of the straight circular portion comprising: a semi-circular expandable portion having a short outwardly flared portion adjacent its small end, and an opposite semi-circular portion having a longer outwardly flared portion leading from its small end; a seamless hollow circular cone shaped entrance portion having its smallest diameter and a mating hole of predetermined size adjacent the split tapered portion; said cone shaped entrance portion integrally connected to the said opposite semi-circular portion and folded around a portion of its largest diameter into and against the said outwardly flared portions and in axial alignment with the said straight circular portion; an opening in the small end of said split tapered portion, smaller than the size of said hole of predetermined size in said seamless cone shaped entrance portion and of the male connector, spaced resilient means projecting above the external surface of the said straight circular portion to prevent axial movement of the receptacle when mounted within a terminal block.

References Cited in the file of this patent UNITED STATES PATENTS Re. 14,401 Andrews Dec. 4, 1917 1,635,256 Carter July 12, 1927 1,768,669 Davis July 1, 1930 2,216,201 Keller- Oct. 1, 1940' 2,223,853 Mebrold Dec. 3, 1940 2,703,872 Doane Mar. 8, 1955 2,779,011 Deakin Jan. 22, 1957 2,813,257 Cornell Nov. 12, 1957 2,814,024 Narozny Nov. 19, 1957 FOREIGN PATENTS 54,552 France Oct. 31, 1949 567,798 Great Britain Mar. 5, 1945 

1. AN INTEGRAL HOLLOW ELECTRICAL RECEPTACLE SPLIT ALONG A PORTION OF ITS LENGTH COMPRISING: A RELATIVELY YIELDABLE PORTION AND A RELATIVELY FIXED PORTION DIAMETRICALLY OPPOSITE ONE ANOTHER; AND A CONTINUOUS ANNULAR ENTRANCE PORTION ADJACENT THE RELATIVELY FIXED PORTION HAVING, A RELATIVELY LARGER LEADING EDGE AND A RELATIVELY SMALLER TRAILING EDGE, FOLDED SOLELY AT AND AROUND A PORTION OF THE SAID LEADING EDGE INTO AND ADJACENT THE INTERNAL SURFACE 